In order to improve the efficiency and fuel consumption of internal combustion engines, control systems for such engines are often controlled in an appropriate manner by electronic engine controllers. Some internal combustion engines have exhaust gas after-treatment systems associated therewith to reduce the emissions of these engines. Such exhaust gas after-treatment systems may be turned on and off at scheduled times by the electronic engine controllers.
Exhaust gas after-treatment systems for diesel engines often include a particulate matter filter system. Particulate matter filter systems developed in recent years make it possible to strongly reduce particle emissions in diesel powered vehicles. For example, some particulate matter filters may remove more than 97% of the particulate matter from the exhaust gas. At certain time intervals, it is necessary to remove soot deposits from a particulate filter so that the flow resistance does not reduce engine performance. To that end, the electronic engine controller can initiate a regeneration process in which a soot layer is burned off. The resulting products of the regeneration process may include, for example, carbon dioxide and water vapor. The controller may also initiate regeneration of other exhaust gas after-treatment devices in the same or similar manner as particulate filters.
Burning off soot during a regeneration process of a filter, or other component, requires high exhaust gas temperatures, such as, for example, temperatures above 550 degrees C. To achieve such high exhaust gas temperatures, the temperature of exhaust gas often is artificial raised via a temperature raising event. Conventionally, temperature raising events include injecting hydrocarbons into the exhaust gas stream upstream of an oxidation catalyst, adjusting the operating parameters of the engine, and activating a heating element in heat transfer communication with the exhaust. Regardless of the type of temperature raising event, active exhaust gas temperature increases for regenerating a particulate matter filter are often necessary to assure reliable ongoing filter operation.
For motor vehicles, the operations associated with regenerating exhaust after-treatment components, such as particulate filters, typically have been initiated at predetermined operation time intervals, predetermined vehicle driving distances, or when an excessive amount of matter accumulated on a component has been detected. Artificially increasing the exhaust gas temperature for regenerating a component can have negative consequences on the performance and efficiency of an engine depending on the operating conditions of the engine at the time the exhaust temperature is raised. However, in conventional systems, the initiation of a regeneration event often is initiated regardless of the operating conditions or driving conditions of the engine. Accordingly, regeneration events, while optimizing the performance of an exhaust gas after-treatment system component, can negatively affect the performance and efficiency of an engine if not coordinated with a current or future operating state of an engine.